The invention relates to a water-cooled multi-cylinder internal-combustion engine. Preferred embodiments of the invention relate to a water-cooled multi-cylinder internal-combustion engine having a crankcase and cooling ducts which surround the cylinders and which are acted upon by coolant by way of a coolant pump in a small cooling circuit, a thermostat being provided for switching over to a large cooling circuit provided with a radiator, which thermostat is inserted in a thermostat housing, the thermostat housing having a top part provided with coolant connection and a bottom part preferably integrated in the crankcase.
From European Patent Document EP 0 933 510 A2, a water-cooled internal-combustion engine is known, in which a thermostat controlling the two cooling circuits is arranged between the two cylinder banks in a thermostat housing surrounding the thermostat. To the extent that it is visible in the drawings, the thermostat housing has a bottom part connected in one piece with a crankcase top half and a thermostat cover to which corresponding inlet and outlet connection pieces are molded. For controlling the two cooling circuits (small cooling circuit—large cooling circuits), corresponding wall sections are provided in the bottom part, by which the corresponding chambers are formed which can be controlled by the thermostat.
It is an object of the invention to develop a housing accommodating the thermostat for a water-cooled multi-cylinder internal-combustion engine, which housing is distinguished by a simple, flow-promoting and weight-optimized construction, which, in addition, requires little space.
The object is achieved by providing a water-cooled multi-cylinder internal-combustion engine having a crankcase and cooling ducts which surround the cylinders and which are acted upon by coolant by way of a coolant pump in a small cooling circuit, a thermostat being provided for switching over to a large cooling circuit provided with a radiator, which thermostat is inserted in a thermostat housing, the thermostat housing having a top part provided with coolant connection and a bottom part preferably integrated in the crankcase, wherein an insertion part is inserted in the bottom part of the thermostat housing, which insertion part has at least one opening which is controlled by a thermostatic valve for controlling the small and the large cooling circuits.
By means of the insertion part suggested according to the invention, water chambers are formed whose openings are monitored by the thermostatic valve. The insertion part is easy to produce, and high-expenditure wall sections, which are normally required in the bottom part of the thermostat housing, can be eliminated.
Additional advantages and advantageous further developments of the invention are contained in the subclaims and in the description.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.